High Availability

This guide is for Apache Hadoop system administrators who want to enable continuous availability by configuring clusters without single points of failure.

Not all Hadoop components currently support highly availability configurations. However, some currently SPOF (single point of failure) components can be configured to restart
automatically in the event of a failure (Auto-Restart Configurable, in the table below). Some components support high availability implicitly because they comprise
distributed processes (identified with an asterisk (*) in the table). In addition, some components depend on external databases which must also be configured to support high availability.